In connection with a motor vehicle, a brake, of course, is any mechanical device for arresting the motion of a wheel (and accordingly the vehicle) by means of friction. Kinetic energy is converted into heat energy through use of frictional forces applied to the wheels of the vehicle, causing the vehicle to slow or stop. A drum brake is a type of brake using a drum-shaped metal cylinder attached to the inner surface of the wheel of a motor vehicle and rotating within it. When the brake is applied, curved brake shoes with friction linings press against the drum's inner circumference to slow or stop the vehicle. The rotating part of a disc brake is also called a “rotor.” The nonrotating, basically stationary, component of a disc brake system is a brake caliper that applies force from a hydraulic system to the rotor or disc to decelerate and stop a vehicle.
Brake fade is a condition brought about by repeated or protracted braking that results in reduced braking effectiveness (fading). Heat is the primary cause of brake fade, which in turn causes expansion and other undesirable thermal effects on a brake. Although disc brakes are less prone to fade because rotors are more effectively cooled by air moving across the brakes, and can be internally vented to increase resistance to fade, nevertheless persistent stop-and-start braking causes damage to any brake, whether a drum or rotor. Accordingly, a significant industry has developed in connection with the machining, refinishing, balancing and resurfacing of brake rotors.
To refinish a brake, a drum or a rotor is mounted on a rotatable shaft or arbor of a brake lathe system. During operation, forces due to rotation and gravity tend to preclude uniform rotation of the rotating arbor on which a brake has been mounted. The arbor and devices mounted on the arbor for refinishing do not rotate in a single, unvarying plane of rotation. The forces acting on a rotating arbor and brake may distort in one or more planes and along one or more axes of rotation. The forces exert a variety of angular and planar forces that affect how accurately and quickly the brake lathe operator may work on a brake to refinish it.
In addition, forces and force vectors may induce harmonics and vibrations that may be transmitted to the arbor, brake and other components of the lathe. A nonuniform rotation of a brake during a refinishing operation may cause a cutting or refinishing tool brought into contact with a brake surface to produce an inferior surface.
To overcome such undesirable problems, the inventor named in this document has received a number of U.S. patents for apparatus and methods that resolve in exemplary fashion adverse consequences of such forces, thus improving the refinishing process, including U.S. Pat. No. 6,279,919B1 issued Aug. 28, 2001 for an Apparatus for Securing a Workpiece to a Rotatable Machine Member; U.S. Pat. No. 6,554,291B1 issued Apr. 29, 2003 for an Apparatus for Securing a Workpiece to a Rotatable Machine Member; U.S. Pat. No. 6,397,989B1 issued on Jun. 4, 2002 for an Apparatus for Reducing Harmonics and Vibrations of a Rotatable Base Piece; U.S. Pat. No. 6,631,660B1 issued Oct. 14, 2003, for a Self-Aligning Arbor Nut System. The inventor currently has pending a U.S. patent application for a Multi-angle Cutting Head, application Ser. No. 10/684,021 filed on Oct. 10, 2003, as well as application Ser. No. 11/365,733 for a Reversible Flange Plate filed on Mar. 1, 2006. The patents and application are collectively referred to in this document as the “Prior Patents” for ease of reference.
The apparatus and method described and claimed in application Ser. No. 11/365,733 for a Reversible Flange Plate adds to the art by providing a flange plate that reduces costs associated with refinishing a rotor by providing on one apparatus differently configured surfaces that allow an operator to reverse the orientation of the flange plate to engage a variety of differently configured brakes.
The apparatus disclosed and claimed in the Prior Patents have proven useful in a variety of situations and installations, and uniquely adapted for uses described in the Prior Patents. Additional optimizations shown and claimed in this document provide an adapter assembly for a hubbed rotor that allows a brake lathe operator to refinish a hubbed rotor of the kind described in this document.
A “hubbed rotor” is a rotor assembly that includes a bearing mechanism that can be connected to an axle, whereas a “hubless” rotor has only a hole in its center and is separate from a hub. A “hubbed rotor” includes at least one bearing mechanism mounted in the rotor and connectable to the axle. A hubbed rotor also includes mounting bolts positioned on the hubbed rotor in numbers, sizes and locations that vary. Mounting bolts are provided, of course, to mount a wheel on a rotor. The adapter assembly for hubbed rotor described and claimed in this document accommodates variations in the number, size and location of mounting bolts. Such variations indicate that neither rotor design nor configuration is standard in the vehicle and automotive industry. Each vehicle manufacturer is free to engineer and design rotors unique to its product line. Ford Motor Company, for example, has introduced a hubbed rotor for use on F-150 vehicles unlike any rotor in the industry.
A hubbed rotor is comparatively expensive. However, for less than ten percent of the cost of replacing a worn hubbed rotor with a new hubbed rotor, a hubbed rotor may be refinished. Currently, however, a hubbed rotor may be refinished only in theory: current tools available for installation on a brake lathe for refinishing rotors cannot accommodate the unique design of some hubbed rotors such as Ford F-150 hubbed rotor. The adapter assembly for a hubbed rotor disclosed and claimed in this document solves the problems associated with refinishing a hubbed rotor.
The problems warranted solving. The Ford F-150 is one of the most popular trucks sold in the United States. For example, in 2004 the Ford F-150 was the top-selling vehicle of any kind in America. According to Automotive News, for the calendar year 2004 Ford Motor Company sold almost 940,000 Ford F-Series units. MSN Autos (http://autos.msn.com) reported that the F-Series has been the best-selling truck in America for 28 straight years. It would appear that Ford F-Series vehicles are and will continue to be a significant factor in the brake refinishing industry for many years. Solving the problems associated with refinishing hubbed rotors will, therefore, save owners considerable money during the operational lives of trucks equipped with a hubbed rotor like that of the F-150. Instead of discarding and replacing expensive hubbed rotors, vehicle owners will have the option to have hubbed rotors refinished for a fraction of the price using the adapter assembly for a hubbed rotor disclosed and claimed in this document.
The adapter assembly for a hubbed rotor is not only easy to assemble on a brake lathe, it is easy to operate. The adapter assembly for a hubbed rotor allows the operator of a brake lathe to produce an accurately and precisely machined, turned and refinished brake. In combination with selected apparatus and methods shown in the Prior Patents, undesirable forces that affect refinishing of a brake may be reduced or eliminated. The adapter assembly for a hubbed rotor also is respectively easy to use and to practice for its intended purposes.